| 1 | Tag Operating Company, Inc. | Houston, TX 77092 | Oil & Gas Operator | Oct 2025 |
| 2 | Talon Development Company | Boerne, TX 78006 | Oil & Gas Operator | Sep 2007 |
| 3 | Talos Gulf Coast Onshore LLC | Houston, TX 77002 | Oil & Gas Operator | Dec 2024 |
| 4 | Tartan Resources Corporation | Houston, TX 77251 | Oil & Gas Operator | Oct 1995 |
| 5 | Taylor-Link Operating Co. | Midland, TX 79702 | Oil & Gas Operator | Apr 2017 |
| 6 | TBC Petroleum | Cuero, TX 77954 | Oil & Gas Operator | Sep 2023 |
| 7 | TC Oil And Gas, LLC | Denton, TX 76205 | Oil Operator | Oct 2025 |
| 8 | TDC Engineering, Inc. | Abilene, TX 79604 | Oil & Gas Operator | Oct 2025 |
| 9 | Te-Ray Resources, Inc. | Oklahoma City, OK 73108 | Oil & Gas Operator | Mar 2015 |
| 10 | Tend Oil Inc. | Tyler, TX 75703 | Oil & Gas Operator | Jul 1995 |
| 11 | Tenex Corporation | Houston, TX 77227 | Oil & Gas Operator | Dec 2007 |
| 12 | Tepee Petroleum Company, Inc. | Houston, TX 77098 | Oil & Gas Operator | Feb 2014 |
| 13 | Texaco E & P Inc | Houston, TX 77099 | Oil & Gas Operator | Oct 2025 |
| 14 | Texana Operating Company | Houston, TX 77090 | Oil & Gas Operator | Oct 2025 |
| 15 | Texas Consolidated Pet. Corp. | Fort Worth, TX 76109 | Oil & Gas Operator | Oct 2025 |
| 16 | Texas Independent Explor., Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2002 |
| 17 | Texas Standard Oil Operating Co. | Midland, TX 79705 | Oil & Gas Operator | Oct 2019 |
| 18 | Texasgulf Inc. | Newgulf, TX 77462 | Oil & Gas Operator | Jul 1994 |
| 19 | Texcal Energy (GP) LLC | Denver, CO 80202 | Oil & Gas Operator | Mar 2016 |
| 20 | Texokan Energy Corporation | Scroggins, TX 75480 | Oil & Gas Operator | Jul 1996 |
| 21 | Texploration | Rosharon, TX 77583 | Oil Operator | Oct 2025 |
| 22 | Texstar North America, Inc. | Waynesboro, MS 39367 | Oil & Gas Operator | Aug 1994 |
| 23 | Thorp Petroleum Corporation | Houston, TX 77002 | Oil & Gas Operator | Feb 2014 |
| 24 | Titan Resources I, Inc. | Midland, TX 79701 | Oil & Gas Operator | Jun 2000 |
| 25 | TMR Exploration, Inc. | Bossier City, LA 71171 | Oil & Gas Operator | Oct 2025 |
| 26 | Tomlinson, Thomas K. Inc. | Port Lavaca, TX 77979 | Oil & Gas Operator | Jul 2003 |
| 27 | Torch Operating Company | Houston, TX 77010 | Oil & Gas Operator | Mar 2015 |
| 28 | Touchstone Resources USA, Inc. | Houston, TX 77002 | Oil & Gas Operator | Oct 2006 |
| 29 | Trans-Pecos Resources, Inc. | Houston, TX 77056 | Oil & Gas Operator | Oct 2025 |
| 30 | Transfuel Resources Co | Houston, TX 77215 | Oil & Gas Operator | Aug 2013 |
| 31 | Transpacific Energy, LLC | Katy, TX 77450 | Oil & Gas Operator | Oct 2025 |
| 32 | Transtexas Gas Corporation | Houston, TX 77265 | Oil & Gas Operator | Aug 2005 |
| 33 | Traton Operating Company | Kingwood, TX 77339 | Oil & Gas Operator | Mar 2019 |
| 34 | Tri-C Resources, Inc. | Houston, TX 77024 | Oil & Gas Operator | Aug 2009 |
| 35 | Tri-C Resources, LLC | Houston, TX 77024 | Oil & Gas Operator | Oct 2025 |
| 36 | Trident Corporation | Woodsboro, TX 78393 | Oil & Gas Operator | Oct 2025 |
| 37 | Triple L Oil Company | Corpus Chrsti, TX 78469 | Oil & Gas Operator | Jan 1998 |
| 38 | Tucker Operating Co., Inc. | Victoria, TX 77903 | Oil & Gas Operator | Oct 2025 |
| 39 | Tuskar (Texas), Inc. | Nichols Hill, OK 73116 | Oil & Gas Operator | Jan 2016 |